Experimental Study On Rheological Properties And Proppant Carrying Capability Of Low Molecular Polymer Fracturing Fluid

Fracturing fluid system plays an important role in the hydraulic fracturing technology.Fracturing fluid is an important factor related to the production effect after fracturing construction.The purpose of this paper is to develop an fracturing fluid system,which has the ability of strong temperature resistance,less damage and so on.This paper through the principle of molecular design,selected three excellent performance monomer for polymerization,and determine the aggregation method for the inverse emulsion polymerization.And the molecular weight of synthetic products is 2.0 million.Because of lower molecular weight,so the synthetic products is called low molecular polymer.Secondly,calculating synthesis of polymer’s fracturing fluid system rheological constitutive equation,get the impact of critical aggregation concentration,the rheological model,the shear resistance of heat-resistant,shear properties,viscoelasticity and thixotropy.The experimental results show that fracturing fluid viscosifier solution exists critical association concentration with 0.15%,and conform to the power law fluid rheological model.The viscosifier solution has good heat-shear resistance and molecular grid structure stability;The fracturing fluid system has excellent heat-shear resistance and viscoelastic.Then,through the filtration performance experiment and nuclear magnetic resonance(NMR),the experiment showed,fracturing fluid system has the ability of low fluid loss and low core damage,and the damage is uniform and small.Finally,by the dynamic and static experiments,we get in different size,different sand ratio and different temperature,low molecular weight polymer fracturing fluid system of suspended sand performance is superior to the guanidine gum fracturing fluid system.And the critical settling velocity and critical suspension velocity is lower than the gum fracturing fluid system in different diameter and different proportion of sand,show the better performance of carrier.Comprehensive,the low molecular weight polymer fracturing fluid system has good rheological properties,filtration performance and low damage performance,which can meet the application requirements.